Since prehistoric times, treatment of human illness and injury has been a factor of human life. Many remedies, whether applied topically or taken by ingestion, were derived from plants or other animals. Broken bones were treated by binding the area to rigid supports, such a splints, casts and the like.
Historically, the success of the treatment of an illness or injury often depended upon its severity. At different points in time, certain illnesses were virtually untreatable resulting in a high fatality rate. Indeed, there are still classes of illnesses today which do not readily respond to known treatments. Likewise, medical personnel at certain historical points in time did not know how to treat conditions such as heart attacks, strokes and the like. The same was true for serious injuries, such as skull fractures, broken necks, etc.
There have been astounding medical advances, however, over the last hundred years, and the advent of new medical procedures and techniques has increased the quality of human life. These advances have occurred in all aspects of medical treatment, and advances are developing at an even accelerated rate. Giant strides have been made in diagnostic equipment to determine the nature of an illness or injury, in procedural techniques to deal with the illness or injury, in pharmaceuticals to treat the illness or injury, and in rehabilitative therapies.
One field of advanced surgery is that performed on the human back, namely, the spine. Surgery on the spine is usually performed in either the lateral recumbent or the prone position. The prone position originally involved the patient being laid recumbent with his/her abdomen on the surface of the operating table. Several disadvantages were present, though, when patients are simply laid face down on the operating surface. For example, it was learned that profuse bleeding could occur due to pressure on the interior vena cava. In addition, having the patient's upper legs generally in line with the torso (the “full prone position”) places compression on the individual vertebra due to the curvature of the spine.
It was learned, then, that blood loss could be reduced by supporting the patient in a prone position with the abdomen pendulous and free. Second, it was learned that elevating the torso relative to the legs with the upper leg inclined at an angle to the torso helped decompress the spinal nerves. This decompression further helped separate the posterior elements of the spinal vertebrae to facilitate any surgery thereon. This position has been referred to as the “flat back/drop knee position”.
In response, numerous devices have been developed to position the human body for back surgery. Significant among these is what is referred to as the “Jackson spinal table” which is depicted in U.S. Pat. No. 5,088,706 issued Feb. 18, 1992 to Jackson. This table allows a patient to be initially positioned in a supine position and then rotated so as to be supported by a prone position by a support structure. The support structure is formed by a plurality of lateral pads which elevate the torso relative to the legs so that the upper leg is inclined thereby decompressing the spine. Since the support pads are posts formed by an open channel, the abdomen is pendulous and free thus helping to reduce bleeding from the surgery. The lower legs are supported on a leg rest in the form of a fabric sleeve or platform extending across the table. Other devices for supporting the torso with the legs inclined for spinal surgery are disclosed in the following patents:
Patent No.Issue DateInventor4,840,362Jan. 20, 1989Bremer et al.5,239,716Aug. 31, 1993Fisk6,076,525Jun. 20, 2000Hoffman
In addition to these patents disclosing structures for spinal surgery, U.S. Pat. No. 6,557,197 issued May 6, 2003 to Graham discloses a support pillow for rectal surgery wherein the torso is elevated relative to the legs.
A problem has arisen, however, when spinal fusion surgery is performed on a patient in the prone position having his/her torso elevated relative to the legs. Namely, when a patient's lumbar spine is fused in the flat back/drop knee position, the patient's sagittal balance may be affected after healing because the fused vertebrae pitch the patient more forwardly.
Therefore, after initial decompression of the spine in the initial surgery, but prior to fusion, it is known to return the patient's legs to the full prone position with the legs linearly aligned with the torso so that the lumbar spine is placed in a more natural curvature before fixation and fusion of the vertebrae. This procedure, however, is not without risk. To accomplish this procedure, a medical personnel typically enters the space underneath the patient to manually lift the patient's knees. Usually, though, this space is replete with neuro-monitoring equipment. This manual procedure can dislodge wires, tubes or other elements of the monitoring equipment risking disruption of the monitoring of the patient's condition. Moreover, there is attendant danger in an abrupt movement of the patient's knees during recompression of the spine. It is more preferable to raise the patient's legs very gradually; however, manually raising the legs in a gradual manner is difficult.
Accordingly, there remains a need for adjunct equipment which may facilitate the positioning of a patient during spinal surgery. There is a further need for apparatus and methods wherein a patient may be initially positioned in a prone position in the flat back/drop knee position who had subsequently moved, in a gradual manner, into the fully prone position prior to spinal fusion. Thus, there remains a need for improved apparatus and methods for conducting spinal surgery. The disclosed embodiments of the present invention are directed to meeting such needs.